Determining the excitation energies of 68Ni Nucleus a Function of the Coupling Angle ¸a,bBy Means of Modified Surface Delta-Interaction

Abstract

In this paper, the nuclear shell model SM was applied to study the energy levels of the nucleus the effect of orbit on energy levels was studied,we consider the residual interaction to be modified surface delta interaction MSDI. We have studied the excitation energies of the 68Ni a nucleus, which contain two neutrons outside closed shell of the 66Ni. the computation of eigenvalues of 68Ni is performed in the frame of (1 p1/2 0g9/2) and (1 _p1/2 0g9/2 0d5/2), we search the effect of the orbital 0d5/2 on the energy levels. The energy levels and angular momentum of all possible cases were investigated. Thus, we have worked on a theoretical process to discover the relation between the energy levels and the classical coupling angle ¸a,b at different orbital within neutron - neutron interaction. Accordingly, We have noticed that the energy levels manifest to follow two inclusive functions, which depend on the classical coupling angles, but are not constrained of angular momentum I. In conclusion, we conclude that our results agree with the experimental data.